Answer:
He reached the top of the tree on the 31st day
Step-by-step explanation:
The total distance for the owl to climb is 93 units.
If the owl climbed 18 units up the tree every day without coming down, the owl would have taken 93/18 days to reach the top of the tree.
However, the owl descends by 15 units every night. This just reduces the overall distance covered at the end of each day's climb.
The net distance covered by the owl after each day is 18-15 units = 3 units of climb. This is the steady distance the owl gains up the three at the end of each day after the ascent and descent.
The time taken for the climb moving at this pace of 3 units per day will be
93 units / 3 units per day = 31 days
